摘要： 为了提高图像去雾算法的运行效率,并解决明亮区域去雾后颜色失真的问题,提出一种基于两次滤波的快速图像去雾算法(TBFIDA)。利用改进的四叉树方法得到鲁棒性强、稳定性好的环境光亮度,在最小通道图中,采用判别式滤波获取粗略的大气散射图,消除光晕现象,使用双边滤波器对粗略的大气散射图作进一步保边平滑优化操作,得到更加精确的大气散射图,并通过容差机制进行透射率修正,解决天空明亮区域去雾后的颜色失真问题。应用大气散射模型形成无雾图像。实验结果表明,TBFIDA能较好地恢复场景的颜色,对景深突变区域也能够保持边缘细节,获得较真实的清晰无雾图像,具有较高的准确性、鲁棒性和实时性。

关键词: 去雾, 暗通道, 四叉树判别式滤波, 双边滤波器, 容差机制

Abstract: In order to improve the running efficiency of image dehazing algorithm and solve the color distortion problem in the bright area after dehazing, this paper puts forward a Fast Image Dehazing Algorithm based on Twice Filtering(TBFIDA).It gets the ambient light brightness with strong robustness and high stability by the improved quadtree method,and obtains a coarse scattering map using the discriminant filtering in minimum channel,eliminating the phenomenon of halo.And it makes full use of bilateral filter for further optimization on edge preserving to get more precise scattering map,followed by using the tolerance mechanism to correct the transmissivity and resolve color distortion in the bright area after dehazing. Finally it gains the fog-degraded image based on the atmospheric scattering model.Experimental results show that TBFIDA algorithm can well restore color,better preserve the edge details of the area with suddenly changed depth of field,and get a real clear no-fog image.It has higher accuracy,robustness,and real-time performance.

Key words: dehazing, dark channel, quadtree discriminant filtering, bilateral filter, tolerance mechanism

中图分类号: 

• TP391.41